4th Exam: Pediatric Pathology

Question 1

Case: blue baby born at 37wk, resp stridor (difficulty), cyanosis, heart murmur, uneventful pregnancy and delivery, healthy 3yo at home

Answer 1

Tetralogy of Fallot

Question 2

Case: 6yo boy, large, weak calves, began tripping and stumbling at 3yo, weakness of arms/thighs at age 4, serum ck elevated 1200 u/l (normal 100) – from muscle (not heart), Gower’s maneuver to stand, brother died at age 12 from same disease

Answer 2

Duchenne’s Dystrophy

Question 3

Case: baby w large abdomen, 2 yo boy, recently losing weight, 100F fever, low energy, abdominal mass, lab: elevated urinary HVA (catecholamine)

Answer 3

Neuroblastoma

Question 4

S-W syndrome sf:

Answer 4

Sturge-Weber Syndrome (malformation of caps)

Question 5

S-W syndrome:

Answer 5

congenital, nonfamilial, born w capillary vascular malformation, too many caps in skin, mouth (port wine stain), facial lesions, usually unilateral, only 10% of pts w port wine stain have S-W (bc it spec includes brain involvement), in one or more divisions of CNV, may involve meninges of brain, seizures

Question 6

S-W Oral Lesions:

Answer 6

Common, not inflammation, but a vascular malformation, gingiva, buccal mucosa

Question 7

Do S-W lesion expand or contract?

Answer 7

No

Question 8

Malformation in S-W lesion consists of:

Answer 8

numerous dilated, proliferations of caps in dermis or submucosa

Question 9

Congenital Heart Disease:

Answer 9

disturbance in heart formation in utero, many causes and types, 1% of live births, many can be corrected by surgery, inc incidence in adults

Question 10

Risk factors for CHD:

Answer 10

Chromo abnormalities (Down’s), molecular abnormalities, maternal status: meds, infections (rubella), diabetes

Question 11

Tetralogy of Fallot (4):

Answer 11

Most common cyanotic heart disease (most common cause of blue baby), VSD (no inter-ventricular septum), pulmonary artery stenosis/ narrowing, flow into lungs restricted, deoxygenated venous blood pumped into systemic circulation, RV gets huge, under pressure, work related hypertrophy, heart murmur, R to L shunt, pt cyanotic, tissues oxygen deprived, hole bw R and L heart → pressure (systolic pressure in baby) is equal between two ventricles (right is higher than normal pressure) → O2 pressure is low and almost equal (60%: RV, 70%: LV) → deoxy blood is going into the L heart

Question 12

Tetralogy Physiology to the body:

Answer 12

Deoxygenated blood shunted from R to L, systemic flow now dec in O2, pt blue (cyanotic) as tissues are O2 deprived

Question 13

Surgery for Tetralogy of Fallot:

Answer 13

Close VSD, open narrowed pulm a., (relieve stenosis, stop communication bw V’s)

Question 14

Muscular Dystrophies:

Answer 14

“faulty nutrition”, heterogeneous disease group (~20)(Duchenne’s, LGMD (Limb-Girdle muscular dystrophy), MyD (myotonic dystrophy), etc.), familial, early onset (1st 5 yrs), usually not present at birth, progressive, never improves, severe weakness, skeletal muscle disease

Question 15

Duchenne Muscular Dystrophy (DMD):

Answer 15

X linked recessive, boys, X chromo, site 21, must have total deletion of dystrophin gene (makes protein), onset: 2-5yo, poor prognosis – often die of heart disease in early 20’s

Question 16

DMD symptoms:

Answer 16

Gower’s maneuver, calf pseudohypertrophy, diagnostic, enlarged, weak, fatty, fibrous infiltration, proximal muscle weakness (trunk) and proximal extremities

Question 17

DMD muscle & heart disease:

Answer 17

hyper-contract, see spaces around them… pre necrosis “pre-hyaline fibers”, pre-necrotic hyaline fibers (pink, rounded), necrotic fibers → macs/phagocytosis, centered nuclei, cardiac fibrosis → heart failure

Question 18

Pathology of DMD, “delta lesion”:

Answer 18

Dystrophin: stabilizes mem, mem assoc protein, prevents rupture during contraction, dystrophin gene deleted from X chromosome, cant make dystrophin, unstable muscle membrane, tiny ruptures in membrane → Extracellular Ca2+ influx → protease activation → death, muscle fibers die, pt becomes weak

Question 19

Neuroblastoma

Answer 19

50% infant tumors, 10% of childhood tumors, median age at dx: 22mo (2 years), molecular abnormalities, abnormalities of N-myc (oncogene), chromosome 2p23, amplification of N-myc = poor prognosis, neural tumors, secrete catecholamines: dopamine, epinephrine, NE, catecholamines in urine, diagnostic, HVA and VMA: metabolic products of catecholamines, EM: secretory granule, neuroendocrine tumors

Question 20

PNETs sf:

Answer 20

Primitive Neuroectodermal Tumors

Question 21

PNETs:

Answer 21

Family of neuroendocrine tumor,small cell carcinoma of the lung (a small cell blue tumor), Neural markers on cells, usually children, all secrete something enlarged abdomen,, neuroblastoma, Medulloblastoma – brain, rentinoblastoma – eye, ewing’s sarcoma – bone

Question 22

Neuroblastoma Pathology (the tumors):

Answer 22

Often arise in adrenal medulla, malignant, grossly soft, bulky, necrotic, hemorrhagic, composed of primitive cells (PNET), embryologic neural crest derivative, small, blue, round cell tumors, many mitoses, necrosis – necrotic tumor coming from adrenal gland, cells may differentiate into neurons (good prognosis), form rosettes = neuronal differentiation

Question 23

Neuroblastoma Behavior:

Answer 23

55% 5y survival, < 2yo: 80% 5y survival (higher for infants), N-myc amplification - poor prognosis, some spontaneously regress, very unusual in mal tumors, some differentiate into neurons = good px, metastasis to (BELL) bone, eye, liver, lungs, 60% of kids present w metastasis

Question 24

Histology of neuroblastoma:

Answer 24

Cellular, sea of small round blue cells, necrosis, many mitoses, rosettes = neuronal differentiation, secretory granules on EM, neuroendocrine granules

Question 25

Neuroblastoma = Neuroendocrine Tumor:

Answer 25

Secretes catecholamines, found in urine, diagnostic, look for metabolites of catecholamines: HVA – homovanillic acid, VMA – vanillylmandelic acid

Question 26

TF? Most kids w port-wine stain have S-W syndrome.

Answer 26

F.

Question 27

Oral mani of S-W syndrome:

Answer 27

hyperemia of B mucosa

Question 28

TF? The S-W lesion will grow in time.

Answer 28

F. not a tumor

Question 29

TF? The R V is under systemic pressure in the tetrolagy of Fallot (TOF):

Answer 29

T.

Question 30

How do P and O2 content vary bw LV and RV in TOF?

Answer 30

100 P in both, 60% oxygenated in RV, 70% in LV

Question 31

TF? A person born today with TOF will most likely only survive until the age of 20.

Answer 31

F we can open pulm a. and patch VSD.

Question 32

What part of the cell is affected in Duchenne muscular dystrophy?

Answer 32

cell membrane

Question 33

Cause of death for most pts w Duchenne’s muscular dystrophy:

Answer 33

severe heart disease, fibers necrose, hypercontracted, fibers die gradually, not all at once, macs come into to digest, tries to regenerate, can’t keep, up, smaller and weaker over time

Question 34

W/o dystrophin, what will happen to a cell when it contracts?

Answer 34

it will tear holes in the membrane, Ca enters, activates protesases that kills the cell

Question 35

Is the px for neuroblastoma better if the pt is young or old?

Answer 35

young

Question 36

Ex of a tumor that can spontaneously regress;

Answer 36

neuroblastoma (1%)

Question 37

Classic presentation of neuroblastoma:

Answer 37

metastesis in eye

Question 38

Origin of tumors:

Answer 38

medulla

Question 39

50% of kids w a protruded abdomen will have:

Answer 39

neuroblastoma

Question 40

Origin of neuroblastoma tumors:

Answer 40

center of adrenal medulla

Question 41

All blue cell tumors make:

Answer 41

rosettes, ring of nuclei around a central focus

Question 42

What type of tumor is the neuroblastoma?

Answer 42

neuroendocrine tumor

Question 43

neuroendocrine tumor:

Answer 43

secrete catecholamines, can be found in urine, represents a dx test, look for metabolites like HVA and VMA, EM show secretory granules

Question 44

Diagnostic of neuroblastoma:

Answer 44

HVA and VMA